The BIOS includes a collection of executable programs and data to initialize other components of a computer system. Upon turning on (or alternatively resetting) the computer system, the computer system executes the BIOS from nonvolatile memory such as read-only memory (ROM) chip(s), or equivalent. In many computer systems, the BIOS loads all or part of the operating system, which is usually stored on the computer system's hard disk. Alternatively, the operating system may be loaded from a compact disc (CD) ROM or a floppy disk. The loaded operating system may subsequently call a BIOS routine or component.
The BIOS (also referred to herein as firmware) in a pre-memory execution environment is usually tightly bound object code that is built for a specific configuration or system design (also referred to herein as a platform). That is, different platforms typically have different BIOSs. More particularly, the BIOS typically includes code (also referred to herein as firmware modules) for providing certain functions or services, which in turn may depend on the platform. For example, the firmware module for a particular service may be different for a platform with a Pentium III® processor compared to one with a Pentium IV® processor. Thus, a BIOS vendor will typically develop several BIOSs to support various platforms, which undesirably increases costs in testing, maintaining and documenting the multiple BIOSs.
Further, the traditional development process requires software developers to compile and link their firmware module with the main firmware executable code. Additionally, the process often requires the software developer to customize the firmware module for each vendor's main firmware executable code. This undesirable process requires the developer to test the firmware module for proper operation in each firmware environment, which tends to increase development time and costs.